‘War is God’s way of teaching Americans geography,” Ambrose Bierce, a Civil War veteran and wicked satirist, supposedly said. The war on terror is no exception.

While the 10th anniversary understandably focused on the loss of those who went to work on 9/11 and never came home, today is also a time to take stock of how America’s mighty response to the attack continues to shape world events. We were asleep for the better part of a decade while Muslim fundamentalists waged war against us, but 9/11 woke the world’s most potent force.

Just as the United States was aroused in other eras to fight fascism and communism, we are engaged again in a worldwide conflict. Historians will one day better understand the ramifications, but already it is clear that the war on terror has shaken the Muslim world as much as the 9/11 attacks convulsed the West. The Arab Spring, to cite one example, owes much of its birth to America’s expanding footprint and the freedom agenda.

One measure of the war’s impact is increased American understanding not only of Mideast geography and history, but also of Islam. Learning the differences between Iraq and Iran, between Sunni and Shia, and, most important, between friend and foe, have been hard-won lessons for both Washington and the public.

Another measure is that 6,234 US soldiers have made the ultimate sacrifice in Iraq and Afghanistan, and more than 45,000 have been wounded. Those wars have cost taxpayers an estimated $1.3 trillion.

It is a huge price in blood and treasure for a result that is maddeningly unsettled. But this much is certain: America got it right by responding to 9/11 with massive military might abroad and hardening our defenses at home.

Osama bin Laden sleeps with the fishes, Saddam Hussein is dead and we and our allies have dealt al Qaeda and other groups serious blows to their operational abilities. Becoming a leader in any terror group is now an automatic death sentence, with justice usually delivered by a drone’s Hellfire missile coming out of the sky in half a dozen countries.

Yes, there were mistakes, big ones, and the invasion of Iraq is still debatable. But try to imagine the world today if we had continued on the feckless course of the Clinton administration, which, obsessed with the president’s personal and political problems, pretended we had little to fear from al Qaeda. The truth is we were already in a war, but didn’t know it until 10 years ago today.

Despite their many differences, Presidents George W. Bush and Obama followed aggressive postures in hunting terrorists around the globe and in building layered defenses here. Neither man sought that responsibility, but both recognized that America’s national security was at stake.

It still hangs in the balance, because bin Ladenism remains a dangerous force. Its adherents are ruthlessly opportunistic, finding footholds in a list of failed and failing states. Somalia, Sudan, Yemen, Lebanon, Gaza, Syria, Libya, Pakistan — all harbor elements of Muslim terrorists. Then there is Egypt, up for grabs in the battle between modernity and savagery.

Yet the fountainhead of terrorism today is Iran, and it is here that America’s mettle ultimately will be tested. Unfortunately, two assumptions of the intelligence and military establishment paint a gloomy picture.

The first is that Obama’s administration, like Bush’s, has concluded it will not use military force to stop the mad mullahs from getting nuclear weapons.

Former Secretary of Defense Robert Gates, who served both presidents, met with King Abdullah of Saudi Arabia during the Bush years and rebuffed requests that America use our military to “cut off the head of the snake.”

Gates, according to former Vice President Dick Cheney, told Abdullah that Bush “would be impeached” if he attacked Iran, a comment that, for all intents and purposes, took the military option off the table. Despite assertions from Obama that he will prevent Iran from getting the bomb, there is no indication he put the military option back on the table.

The second assumption flows from the first. It is that Iran, once it gets the bomb, will precipitate a nuclear war. It might involve a strike on Israel, which has its own arsenal and would surely retaliate, if it doesn’t strike Iran first.

Or a war could happen in a matter of years, and involve other countries, like Saudi Arabia, which has said it would get nuclear weapons if Iran does.

Either way, the prospect of a nuclear winter looms. And so, a decade after our war on terror began, there is no sign of when it will end, or how.

O goes negative on the nation

In his jobs speech, President Obama displayed the higher level of energy demanded by the left. The speech also had another feature libs had to love: extreme negativity about America.

Obama talked down the nation in ways that were dispiriting and exaggerated. After sketching past eras where “hard work and responsibility paid off,” he said, “If you did the right thing, you could make it — anybody could make it in America.”

His suggestion that this is no longer the land of opportunity is a steaming pile of manure. Sure, times are tough for many, but to say the basic promise of America has ended is false. Otherwise, why do so many foreigners still come here?

Besides, it’s odd to hear the first black president extol pre-civil-rights days as the golden age.

He praised China for building airports and railroads, and strangely said “it’s an outrage” that “our skies are the most congested in the world,” as though we should build more skies. Hmmm.

He said schools need to be renovated, then offered a wholesale excuse for failure, asking, “How can we expect our kids to do their best in places that are literally falling apart?”

There was the predictable call for tax hikes on oil companies and “millionaires and billionaires,” to which he quickly added the Big Lie: “This isn’t class warfare.” Right.

The president is an unhappy warrior, and going negative against the country is straight out of the ObamaCare playbook. Then he insisted the “system is broken,” even though 85 percent of Americans were satisfied with their health care. He concocted a false story about an insurance company turning down his dying mother for coverage and accused doctors of performing unneeded surgeries out of greed.

Perhaps he would be happier as president of China.

Weiner replace a dem disgrace

It’s easy to understand why Democrat David Weprin is trailing Republican Bob Turner in the congressional race to replace the shamed Anthony Weiner. The 37 Dems that Weprin’s Web site says endorsed him range from Gov. Cuomo, Sens. Schumer and Gillibrand to a gaggle of City Council members — but they all share something.

Not a single one of the 37 called on Weiner to resign during his crotch-shot scandal. If it were up to them, Weiner still would be in Congress. Theirs is not an endorsement of good judgment.